Elastic tube alignment system for precisely locating components

ABSTRACT

An elastic tube alignment system for the mating of components utilizing the principle of elastic averaging. A plurality of geometrically separated elastic tube (male) alignment features are disposed on a first component, while a plurality of one-to-one corresponding aperture (female) alignment features are provided on a second component. During the mating of the components, each elastic tube and its respective aperture provide elastic deformation, which, on average, precisely aligns the components.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit U.S. application Ser. No. 13/187,675filed Jul. 21, 2011 and published as U.S. Pub. No. 2013/0019455, thecontents of which are incorporated herein by reference thereto.

TECHNICAL FIELD

The present invention relates to location features for aligning ofcomponents during a mating operation. More particularly, the presentinvention relates to a plurality of mutually spaced apart elastic tubealignment features of a first component which elastically deform onaverage when mated to receiving aperture alignment features of a secondcomponent to thereby precisely align the first and second componentsduring a mating operation.

BACKGROUND OF THE INVENTION

Currently, components which are to be mated together in a manufacturingprocess are mutually located with respect to each other by 2-way and/or4-way male alignment features, typically upstanding bosses, which arereceived into corresponding female alignment features, typicallyapertures in the form of holes or slots. There is a clearance betweenthe male alignment features and their respective female alignmentfeatures which is predetermined to match anticipated size and positionalvariation tolerances of the male and female alignment features as aresult of manufacturing (or fabrication) variances. As a result, therecan occur significant positional variation as between the mated firstand second components which contributes to the presence of undesirablylarge and varying gaps and otherwise poor fit therebetween.

By way of example, FIGS. 1 through 3 illustrate the prior art locationmodality for the aligning of two components as they are being mutuallymated.

A first component 10 has a plurality of male alignment features in theform of an upstanding elongated rib 12 and spaced therefrom anupstanding four-pronged stud 14. A second component 16 has a pluralityof female alignment features in the form of a narrow slot 18 disposed atan end and a wide slot 20 disposed at the opposite end. The additionalslots 22 of the second component 16 are intended to provide clearancefor threaded fasteners 24 to be screwed into screw receiving holes 26 ofthe first component 10.

As best shown at FIG. 2, the elongated rib 12 is loosely received intothe narrow slot 18, wherein the spacing 30 between the sides 18′ of thenarrow slot and the sides 12′ of the elongated rib allow spacingtherebetween for accommodating manufacturing variances. Similarly, asbest shown at FIG. 3, the pronged stud 14 is loosely received into thewide slot 20, wherein the spacing 30 between the sides 20′ of the wideslot and the sides 14″ of the prongs 14′ of the pronged stud allowspacing therebetween for accommodating manufacturing variances. Forexample, the spacing (or gap, or clearance) 30 between the male andfemale alignment features may be 0.6 mm, whereby the error of mating ofthe first component to the second component may be up to about 1.2 mm asa cross-car and up-down float.

In operation, as the first and second components are mated together, theinitial contact therebetween occurs when the elongated rib passes intothe narrow slot and the pronged stud passes into the wide slot, wherebythe first and second components are brought into a general alignment toone another. The larger size of the narrow slot in relation to theelongated rib and the larger size of the wide slot in relation to thepronged stud allow the mating to proceed smoothly and effortlessly asthe first and second components mate, even if there is presentmanufacturing variance in terms of size and position of the alignmentfeatures. Problematically, however, there is considerable float asbetween the elongated rib in relation to the narrow slot and as betweenthe pronged stud and the wide slot. This float (or play), as mentionedabove, allows for the first component to be aligned relative to thesecond component generally, but not precisely. When the threadedfasteners are screwed in, any misfit of alignment becomes manifest, andthe visible joint between the two components may be irregular, have toolarge a gap, be unbalanced in appearance, etc., in any event the misfitof alignment rendering the fit unacceptable for a Class A finish.

Accordingly, what remains needed in the art is to somehow provide analignment modality for the mating of components, wherein when mating iscompleted there is a lack of play as between the male and femalealignment features so as to provide a precision alignment, yet thealigned mating proceeds smoothly and effortlessly each time.

SUMMARY OF THE INVENTION

The present invention is an elastic tube alignment system for theprecise mating of components, particularly motor vehicle components,wherein when mating is completed there is a lack of float (or play) asbetween the male and female alignment features so as to provide aprecision alignment with stiffened positional constraint, yet thealigned mating proceeds smoothly and effortlessly each time.

The elastic tube alignment system according to the present inventionoperates on the principle of elastic averaging. A plurality ofgeometrically separated elastic tube (male) alignment features aredisposed on a first component, while a plurality of one-to-onecorresponding aperture (female) alignment features are provided on asecond component, wherein the elastic tube alignment features have adiameter exceeding a cross-section of the aperture alignment features.However, the first and second components may each have some of theelastic tube alignment features and some of the aperture alignmentfeatures so long as they one-to-one correspond so that they are mutuallyengageable with one another. During the mating of the first component tothe second component, each elastic tube alignment feature respectivelyengages its corresponding aperture alignment feature. As the elastictube alignment features are received into the aperture alignmentfeatures, any manufacturing variance in terms of position and size ofthe elastic tube and aperture alignment features is accommodated byelastic deformation, on average, at the interface between the elastictube and aperture alignment features. This elastic averaging across theplurality of elastic tube and aperture alignment features provides aprecise alignment as between the first and second components when theyare mated relative to each other, and yet the mating proceeds smoothlyand easily.

In accordance with the present invention, the elastic averaging providesa precise alignment of the components within a variance X′, defined byX′=X/√N, where X is the average manufacturing variance of the elastictube alignment features and the aperture alignment features, and N isthe number thereof. Thus, the needed clearance for the male and femalealignment features of the prior art is obviated by the presentinvention.

According to the present invention, the elastic tube alignment featuresare elastically deformable by elastic compression of the tube wall ofthe elastic tube, which deformation is preferably resilientlyreversible. In an exemplar application of the present invention, theelastic tube alignment features are connected (typically integrally)with a first component in upstanding, perpendicular relation to apredetermined surface of the first component. Further according to thepresent invention, it is possible, but not required, for the aperturealignment members to be elastically deformable by elastic expansion ofthe aperture wall of the aperture, which deformation is preferablyresiliently reversible. In an exemplar application of the presentinvention, the aperture alignment features are disposed at a secondcomponent, typically as a slot or a hole in a predetermined surface ofthe second component, wherein the diameter of the elastic tube alignmentfeatures exceeds the cross-section of the aperture alignment features,whereby elastic deformation occurs as each elastic tube alignmentfeature is received into its respective aperture alignment feature. Theprocess of mating with precise alignment is both smoothly and easilyperformed. This is enhanced by a tapering (smaller diameter withincreasing height) of the elastic tube alignment features so as tofacilitate their initial entry into the aperture alignment features, andby beveling of the aperture wall of the aperture alignment features soas to locally pronounce the elastic deformation at the interface of theaperture wall with the tube wall.

In operation, as the first and second components are mated together, theinitial contact therebetween is at the plurality of geometrically spacedapart elastic tube alignment members passing into their one-to-onecorresponding aperture alignment features. Because of the larger size ofthe diameter of elastic tube alignment features relative to thecross-section of the aperture alignment features, an elastic deformationoccurs at the interface therebetween, and this deformation is averagedover the geometrical distribution of the plurality of elastic tubealignment features. The alignment becomes precise when the first andsecond components have fully mated because the tapering of the elastictube alignment features provides a largest diameter to the cross-sectionof the aperture alignment features when the first and second componentshave arrived at final mating. When an affixment modality is implemented,such as for example threaded fasteners, heat staking, sonic welding,push nuts, clips, etc., the precise alignment becomes manifest, and thevisible joint between the two components is a perfect Class A finish.

Accordingly, it is an object of the present invention to provide anelastic tube alignment modality for the mating of components, whereinwhen mating is completed there is a lack of play as between the elastictube and aperture alignment features so as to thereby provide aprecision alignment, yet the mating proceeds smoothly and effortlessly.

This and additional objects, features and advantages of the presentinvention will become clearer from the following specification of apreferred embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a first component generally aligned to asecond component before final assembly by threaded fasteners, wherein aprior art alignment modality is utilized.

FIG. 2 is a detail, cut-away view, seen at demarcation 2 of FIG. 1.

FIG. 3 is a detail, cut-away view, seen at demarcation 3 of FIG. 1.

FIG. 4 is a perspective view of a first component generally aligned to asecond component before final assembly by threaded fasteners, whereinthe view is similar to FIG. 1 except now an elastic tube alignmentsystem according to the present invention is utilized.

FIG. 5 is a partly sectional view, seen along line 5-5 of FIG. 4.

FIG. 6 is a partly sectional view, similar to FIG. 5, wherein a firststage of mating between the first and second components is shown.

FIG. 7 is a partly sectional view, similar to FIG. 5, wherein a middlestage of mating between the first and second components is shown.

FIG. 8 is a partly sectional view, similar to FIG. 5, wherein a finalstage of mating between the first and second components is shown.

FIG. 9 is a plan view of a Class B rear side of a first alternatecomponent having a plurality of elastic tube alignment featuresaccording to the present invention.

FIG. 10 is a plan view of a Class B rear side of a second alternatecomponent having a plurality of aperture alignment features according tothe present invention in one-to-one correspondence to the plurality ofelastic tube alignment features of FIG. 9.

FIG. 11 is plan view of the Class B rear side of the first and secondalternate components now mated to each other utilizing elastic averagingof deformation of the elastic tube and aperture alignment features ofFIGS. 9 and 10 according to the present invention.

FIG. 12 is a plan view of the Class A front side of the first and secondalternate components mated as in FIG. 11.

FIG. 13 is a detail view, seen at demarcation 13 of FIG. 11.

FIG. 14 is plan view of the Class B rear side of the first and secondalternate components now mated to each other, as in FIG. 11, now affixedto each other by heat stacking, and now additionally showing a thirdcomponent mated to the first and second alternate components includingalignment therewith via elastic averaging of deformation of the elastictube and aperture alignment features according to the present invention.

FIG. 15 is a partly sectional view similar to FIG. 5, wherein now thefirst and second components each have an elastic tube and aperturealignment feature according to the present invention.

FIG. 16 is a top plan view of a trilobular shaped elastic tube alignmentfeature according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the Drawing, FIGS. 4 through 14 depict various examplesof the structure and function of the elastic tube alignment systemaccording to the present invention.

Referring firstly to FIGS. 4 through 8, the general principles of theelastic tube alignment system 100 according to the present inventionwill be detailed, wherein the elastic tube alignment system operates onthe principle of elastic averaging.

A plurality of mutually separated elastic tube alignment features(serving as male alignment features) 102 (hereinafter referred to simplyas “elastic tubes”) are disposed on a first surface 104 of a firstcomponent 106. As best shown at FIG. 5, the elastic tubes 102 areupstanding in normal relation to the first surface 104, wherein amutually separated pair of elastic tubes is disposed at both a left end106′ and a right end 106″ of the first component 106. Each of theelastic tubes 102 is tubular in shape, having a tube wall 102′.Preferably, the tube wall 102′ defines a hollow cylinder. The tube wall102′ is elastic, being preferably stiffly elastic, wherein the shape isresiliently reversible in response to a compressive force being appliedthereto. A preferred plastic material is one having elastic propertiesso as to deform without fracture, as for example acrylonitrile butadienestyrene (ABS).

A plurality of aperture alignment features (serving as female alignmentfeatures) 110 (hereinafter referred to simply as “apertures”) aredisposed in a second surface 112 of a second component 114, beinglocated in one-to-one correspondence with the plurality of elastic tubes102; that is, for each elastic tube is a respective aperture into whichit is receivable. Thus, the plurality of apertures are geometricallydistributed in coordinated relationship to a geometrical distribution ofthe plurality of elastic tubes such that each elastic tube is receivableinto its respect aperture. While the apertures 110 are shown aselongated slots, it is clear the aperture shape could be otherwise, suchas for example an elongated hole, a generally round hole, etc.Preferably, an aperture wall 116 which defines the opening demarcationof the aperture alignment features 102 is beveled 116′. A preferredplastic material for the second component 114 in which the apertures 110are disposed is one having elastic properties so as to deform withoutfracture, as for example acrylonitrile butadiene styrene (ABS).

While it is preferred for the first and second components 106, 114 to bemotor vehicle components, this is not a requirement.

As depicted at FIG. 6, the diameter 130 of the elastic tubes 102 exceedsa cross-section 132 of the apertures 110, whereby elastic deformationproceeds as each elastic tube is received into its respective aperture.As best shown at FIG. 5, the elastic deformation of the tube wall 102′is locally pronounced due to the beveling 116′ of the aperture wall 116,wherein there is provided a relatively small contact area as between theaperture wall contact surface 116″ and the tube wall 102′ (see FIG. 5).Since the compressive force between the aperture wall and the tube wallis limited to the smaller surface area of the aperture wall contactsurface, a higher compressive pressure is provided, see for example theelastic deformation 136 shown at FIGS. 5, 7 and 8.

The process of mating the first component 106 to the second component114 is both smoothly and easily performed, facilitated by a tapering(smaller diameter with increasing height, as shown comparatively at FIG.6 by distal and proximal diameters 130′ and 130″ of the distal andproximal ends 102″, 102′ of the tube wall 102′. In this regard, thetapering of the elastic tubes presents a largest diameter 130″ at thecross-section of the apertures when the first and second components havearrived at final mating; further, the tapering may present a smallestdiameter 130′ of the tube wall at the distal end 102″ so as to easeinitial entry of the elastic tubes into the apertures.

During the mating of the first component 106 to the second component114, each elastic tube 102 respectively engages its correspondingaperture 110, wherein as the elastic tubes pass into the apertures, anymanufacturing variance in terms of position and size thereof isaccommodated by elastic deformation on average of the plurality ofelastic tubes and apertures. This elastic averaging across the pluralityof elastic tubes and apertures 102, 110 provides a precise alignment asbetween the first and second components 106, 114 when they are finallymated relative to each other.

According to the present invention, the elastic averaging provideselastic deformation of the interface between the plurality ofgeometrically distributed elastic tube alignment features 102 and theaperture alignment features 110, wherein the average deformationprovides a precise alignment, the manufacturing variance being minimizedto X′, defined by X′=X/√N, where X is the manufacturing variance of theelastic tube and aperture alignment features and N is the numberthereof.

Further according to the present invention, it is possible, but notrequired, for the aperture alignment members 110 to be also elasticallydeformable by elastic expansion of the aperture sidewall, whichdeformation is also preferably reversible; see for example 110′ at FIG.5.

Referring now to FIGS. 6 through 8, operation of the elastic tubealignment system 100 according to the present invention will bedetailed.

As seen at FIG. 6, the first and second components 106, 114 are broughtinto close proximity with near alignment. Referring next to FIG. 7, asthe first and second components 106, 114 are mated together, the initialcontact therebetween is via the plurality of geometrically spaced apartelastic tubes 102 passing into their one-to-one corresponding apertures110, whereduring the first and second components align to one another.The alignment is precise at FIG. 8, wherein the first and secondcomponents 106, 114 have now fully mated. The alignment is precisebecause of the largest size diameter of elastic tubes relative to thecross-section of the apertures results in elastic deformation, and thiselastic deformation is elastic averaged over the plurality ofgeometrically distributed elastic tubes. When an affixment modality isimplemented, such as for example threaded fasteners (see bolts 140 inFIGS. 4 and 5), heat staking, sonic welding, etc., the precise alignmentbecomes manifest, and the visible joint between the two components is aperfect Class A finish.

A comparison between FIGS. 1 and 4 brings attention to the advantage ofthe elastic tube alignment system 100 over the prior art alignmentmodality, wherein the present invention provides a stiffer assemblyinherently without float, whereby, for example only two threadedfasteners 140 are needed, as opposed to four in the assembly of FIG. 1.

Turning attention now to FIGS. 9 through 14 a second example forimplementing the elastic tube alignment system 100 according to thepresent invention will be detailed.

As shown at FIG. 9, a first, or base, component 200 has a Class B baserear surface 202. A plurality of geometrically distributed elastic tubealignment features 204 are upstanding in perpendicular relation to thebase rear surface 202, being integrally formed therewith. As shown atFIG. 10, a second, or bezel, component 206 has a Class B bezel rear side208. A plurality of geometrically distributed aperture alignmentfeatures 210 are formed in the bezel component.

As depicted at FIG. 11, the base and bezel components 200, 206 have beenaligned relative to each other by elastic average deformation of theelastic tube features 204 interfacing with the aperture alignmentfeatures 210 according to the elastic tube alignment system 100 of thepresent invention, whereby the base component is precisely aligned withrespect to the bezel component, having the aforementioned reducedmanufacturing variance of X′=X/√N.

The result of the precise alignment provided by the elastic averaging isdepicted at FIG. 12 which shows the opposite, visible Class A side,wherein the visible joint 214 between the base and bezel components 200,204 has everywhere a perfect fit because of the elastic averaging of theelastic tubes with the apertures according to the present invention.

As can best be seen by simultaneous reference to FIGS. 11, 12 and 13,the visible joint has local joint components disposed adjacent eachelastic tube and its respective aperture. For example, the elastic tubesand apertures 204, 210 at demarcation 13 of FIG. 11 is disposed adjacenta local joint component 220 of the visible joint 214 of FIG. 12. Asshown at FIG. 13, the aperture alignment feature 210 has an elongationaxis 224 that is oriented parallel to the local joint component 220,wherein the length exceeds the diameter 230 of the elastic tubealignment feature 204. The cross-section 226 of the aperture alignmentfeature 210 is oriented perpendicular to the local joint component 220,wherein the cross-section has a length less than the diameter 230, thusassuring elastic deformation 232, due to compressive force 234, will beapplied by the aperture alignment feature to the elastic tube alignmentfeature perpendicular to the elongation axis and the orientation of thelocal joint component 220, thereby assuring there is provided a Class Afit at the visible joint.

Turning attention lastly to FIG. 14, some or all the elastic tubes areheat staked 238 to affix the base component to the bezel component. Nowadditionally, a third component 240 has been affixed to the previouslyaffixed base and bezel components. In this regard, firstly a pair ofelastic tubes 244 of the base component 200 are received into apertures246 of the third component 240, wherein as the elastic tubes arereceived into the apertures in accordance with the elastic tubealignment system 100, wherein elastic averaging occurs as describedabove. Once fully mated with a precise alignment, threaded fasteners 248are threadably engaged into screw receiving holes of the base component200.

The elastic tubes 102 and the apertures 110 may reside on either of thefirst and second components, and indeed, some elastic tubes and someapertures may be present at both the first and second components. By wayof example, FIG. 15 is a view as in FIG. 5, wherein now the elastic tubealignment system 100 is characterized by the first component 1061 havingboth an elastic tube and an aperture, while, likewise, the secondcomponent 1141 having also both an elastic tube and an aperture.

Additionally, while cylindrical elastic tubes are preferred, the shapemay be non-cylindrical. For example, as shown at FIG. 16, an elastictube 1021 in accordance with the present invention may have a trilobularshape and may or may not have varying thickness of the tube wall.

It will be understood from the foregoing description, several notableaspects of the present invention. The present invention: 1) eliminatesthe manufacturing variation associated with the clearances needed for a2-way and 4-way locating schemes of the prior art; 2) reduces themanufacturing variation by elastically averaging the positionalvariation; 3) eliminates the float of components as is present in theprior art; 4) provides an over constrained condition that reduces thepositional variation by averaging out each locating features variation,and additionally stiffens the joint reducing the number of neededfasteners; 5) provides more precise location of components; and, 6)provides a stiffened assembly of the mated first and second componentswith elimination of rattle between the components in elastic deformationwith respect to each other.

To those skilled in the art to which this invention appertains, theabove described preferred embodiment may be subject to change ormodification. Such change or modification can be carried out withoutdeparting from the scope of the invention, which is intended to belimited only by the scope of the appended claims.

What is claimed is:
 1. A method of aligning components to each other,the method comprising: providing a first component having a plurality ofupstanding elastic tubes; providing a second component having aplurality of apertures formed therein, wherein the plurality ofapertures are geometrically distributed in coordinated relationship to ageometrical distribution of the plurality of elastic tubes such thateach elastic tube of the plurality of elastic tubes is receivable into arespective aperture of the plurality of apertures; mating the firstcomponent to the second component, whereduring the first component isaligned to the second component by each elastic tube of the plurality ofelastic tubes into its respective aperture of the plurality ofapertures; elastically deforming an interface between each elastic tubeof the plurality of elastic tubes and its respective aperture of theplurality of apertures; and elastic averaging the elastic deformationover the plurality of elastic tubes such that upon mating, a preciselocation of the first component to the second component transpires. 2.The method of claim 1, wherein said step of elastically deformingcomprises resiliently reversible elastic deformation of each elastictube.
 3. The method of claim 2, wherein said step of mating forms ajoint between the first and second components, and wherein the elasticdeformation during said step of elastically deforming occurs generallyperpendicular to a respectively adjacent local component of the joint.4. The method of claim 2, wherein in said steps of providing, amanufacturing variance of size and position of the plurality of elastictubes and the plurality of apertures occurs, wherein the manufacturingvariance has an average length of X, and wherein said step of elasticaveraging provides a reduced manufacturing variance of length X′,wherein X′=X√N, wherein N is the number of elastic tubes of theplurality of elastic tubes.
 5. The method of claim 1, further comprisingheat staking at least one elastic tube of the plurality of elastic tubesto at least one of the first component and the second component.
 6. Amethod for precisely aligning components of a motor vehicle during amating operation, said method comprising the steps of: providing a firstvehicle component; providing a second vehicle component, wherein in saidsteps of providing, either of said first and second vehicle componentsare provided with a plurality of upstanding elastic tubes and aplurality of apertures formed therein, wherein the plurality ofapertures are geometrically distributed in coordinated relationship to ageometrical distribution of the plurality of elastic tubes such thateach elastic tube is receivable into a respective aperture; mating thefirst vehicle component to the second vehicle component, whereduring thefirst vehicle component is aligned to the second vehicle component byeach said elastic tube being received into its respective aperture;elastically deforming an interface between each elastic tube and itsrespective aperture; and elastic averaging the elastic deformation overthe plurality of elastic tubes such that upon mating, a precise locationof the first vehicle component to the second vehicle componenttranspires.
 7. The method of claim 6, wherein said step of elasticallydeforming comprises resiliently reversible elastic deformation of eachelastic tube.
 8. The method of claim 7, wherein said step of matingforms a joint between said first and second vehicle components, andwherein the elastic deformation during said step of elasticallydeforming occurs generally perpendicular to a respectively adjacentlocal component of the joint.
 9. The method of claim 7, wherein in saidsteps of providing, a manufacturing variance of size and position of theelastic tubes and the apertures occurs, wherein the manufacturingvariance has an average length of X, and wherein said step of elasticaveraging provides a reduced manufacturing variance of length X′, whereX′=X/√N, wherein N is the number of the elastic tubes.
 10. The method ofclaim 6, further comprising heat staking at least one elastic tube ofthe plurality of elastic tubes to at least one of the first componentand the second component.
 11. A method of manufacturing an elasticaveraging alignment system, the method comprising: forming a firstcomponent comprising an alignment member; forming a second componentcomprising an alignment aperture, wherein the alignment member isconfigured for insertion into the alignment aperture; and forming thealignment member from an elastically deformable material such that whenthe alignment member is inserted into the alignment aperture, thealignment member elastically deforms to an elastically averaged finalconfiguration to facilitate aligning the first component relative to thesecond component in a desired orientation.
 12. The method of claim 11,further comprising: forming the first component with a plurality of theelastically deformable alignment member; and forming the secondcomponent with a plurality of the alignment aperture, the plurality ofalignment members being geometrically distributed with respect torespective ones of the plurality of alignment apertures, such thatportions of the elastically deformable alignment members, when engagedwith respective ones of the plurality of alignment apertures,elastically deform to an elastically averaged final configuration thatfurther aligns the first component with the second component in thedesired orientation.
 13. The method of claim 11, further comprisingforming the alignment member as a tube.
 14. The method of claim 13,further comprising forming the tubular alignment member such that a tubewall tapers from a first end of the tubular alignment member to a secondend of the alignment member.
 15. The method of claim 11, furthercomprising forming the alignment member and an aperture wall of thealignment aperture from the elastically deformable material such thatthe elastic deformation comprises resiliently reversible elasticdeformation of the alignment member and the aperture wall.